Nick Gorham wrote:
The interesting thing there, is the statement that because it seems some
may prefer 2nd harmonics, this means that it "casts doubt on subjective
testing", not that it casts doubt on the validity of the measurement of
distortion :-)

In other words, the people who prefer the distortion are wrong,

Of course not but they cannot use the sound they prefer to judge how
well an amplifier is performing.

and they should be ignored.

If they are using this to judge the performance of the amplifier then
probably. If they are using it to judge what sound they prefer then
probably not.

And it clearly indicates that his goal was the
production of an amplifier that measured well, not one that people liked
to listen to.

Measured well is perjorative but essentially correct. The function of
an amplifier is to amplify the signal without distortion. If you want
to amplify the signal and distort it in a nice sounding way then all
competent engineers and rational people will separate the two functions
and assess them separately.